Jest/TypeORM purge database after all tests

Question

I would like to delete all entries into my database after or before all jest tests.

Here is my setup.js:

import { getConnection, getConnectionManager } from "typeorm"

beforeAll(async () => {
    const connectionManager = getConnectionManager()
    const connection = connectionManager.create({
        "type": "postgres",
        "host": "localhost",
        "port": 54320,
        "username": "test",
        "password": "test",
        "database": "test",
        "entities": ["../src/entities/*.ts"],
        "logging": false,
        "synchronize": true
    })
    await connection.connect()
})

afterAll(async () => {
    await getConnection().close()
})

I read on the typeorm documentation that the "synchronize" option would override the old tables with new one which are empty but it doesn't seems to work.

Here is the test I made:

describe('POST /create', () => {
    it('Create a user', async () => {
        const user: IStringTMap<string> = {
            firstName: 'John',
            lastName: 'Doe',
            email: '[email protected]',
            password: 'test123!',
        }

        const res: Response = await request(app)
            .post('/create')
            .send(user)
            .expect(200)

        expect(res.type).toEqual('application/json')
        expect(res.body.email).toBe('[email protected]')
        expect(res.body.password).toBe(undefined)
    })
})

First yarn test works but the next one doesn't (email already exists)

Any idea?

Answer 1

Maybe a little late but was searching for this as well, this is what I came up with.

This will only delete the content inside the entities, not the entities itself.

afterEach(async () => {

    // Fetch all the entities
    const entities = getConnection().entityMetadatas;

    for (const entity of entities) {
        const repository = getConnection().getRepository(entity.name); // Get repository
        await repository.clear(); // Clear each entity table's content
    }
});

---

EDIT: If you're using foreign keys, make sure to add the {onDelete: "CASCADE"} property to your columns in order to delete all the records correctly.

More information about that can be found here: https://github.com/typeorm/typeorm/issues/1460#issuecomment-366982161

Answer 2

you can setup a new database in your e2e test file with a separate name and set the dropSchema: true option when you import the typeorm module. you can import the typeorm module int he imports the same way you do in AppModule

Answer 3

Here is a simple and efficient way to fully clean a DB with typeorm, in creating a dedicated TestService which TRUNCATE all entities in one command:

import { Inject, Injectable } from "@nestjs/common";
import { Connection } from "typeorm";

@Injectable()
export class TestService {
  constructor(@Inject("Connection") public connection: Connection) {}

  public async cleanDatabase(): Promise<void> {
    try {
      const entities = this.connection.entityMetadatas;
      const tableNames = entities.map((entity) => `"${entity.tableName}"`).join(", ");
      
      await this.connection.query(`TRUNCATE ${tableNames} CASCADE;`);
      console.log("[TEST DATABASE]: Clean");
    } catch (error) {
      throw new Error(`ERROR: Cleaning test database: ${error}`);
    }
  }
}

Then you can call this function in your testing files:

beforeEach(async () => {
  await testService.cleanDatabase();
});